A decijoule (dJ) is a metric-prefixed unit of energy equal to 10-1 joules, a fraction of a single joule, using the SI deci prefix.
Decijoules to Millijoules
Convert Decijoule (dJ) to Millijoule (mJ) instantly with an exact formula, conversion table, and FAQ.
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Convert decijoules (dJ) to millijoules (mJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
mJ = dJ × 100
Results update instantly for Decijoules to Millijoules conversions.
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Formula
mJ = dJ × 100
dJ = mJ × 0.01
Conversion table
| 1 dJ | 100 mJ |
| 5 dJ | 500 mJ |
| 10 dJ | 1000 mJ |
| 20 dJ | 2000 mJ |
| 50 dJ | 5000 mJ |
| 100 dJ | 10000 mJ |
| 500 dJ | 50000 mJ |
| 1000 dJ | 100000 mJ |
Related conversions
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How the formula works
Both decijoule and millijoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in decijoules by 100 to get millijoules. To reverse the conversion, multiply a millijoule value by 0.01 to get back to decijoules.
Frequently asked questions
What is Decijoule (dJ)?
A decijoule (dJ) is a metric-prefixed unit of energy equal to 10-1 joules, a fraction of a single joule, using the SI deci prefix.
What is Millijoule (mJ)?
A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
How do I convert decijoules to millijoules?
Multiply the decijoule value by 100 to get the equivalent in millijoules. For example, 5 dJ × 100 = 500 mJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 100 is an exact, non-rounded value.
Can I convert millijoules back to decijoules?
Yes. Divide the millijoule value by 100, or multiply it by 0.01, to get decijoules.
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About converting decijoules to millijoules
A decijoule (dJ) is a metric-prefixed unit of energy equal to 10-1 joules, a fraction of a single joule, using the SI deci prefix. A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
Use this calculator to move between decijoules and millijoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.